Carburetor



Jan. 24, 1956 Filed DeG. 19, 1952 c. L. wENTz, JR 2,732,193

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ATTOQLI EYB Jan. 24, 1956 c. L. wENTz, JR

CARBURETOR 3 Sheets-Sheet 3 Filed DSG. 19. 1952 Y. Q KJ ma M j@ m2 mw fm n l o.. Fi Q i HMA r C a E 2 f C M Q) Q /Q Z J e 6 2 A 2, a m ivf V m l|. J2 m q E is@ l @so l @im United States Patent Otice 2,732,193 latented Jan, 24, 19,56

cAnBuRnrol- CeciliLt Went-z, jr., Sheridan, Wyo. Application Datenbasis, 195i, Serial' No. 326,902

This invention relates to carburetors, and more particularly, has' reference" t'o a carburetor having an adjustable venturi, so arranged as to improve' fuel vaporiz'ation.

Summarized very briey, the" present invention' includes a carburetor arrarigenl'eht` wherein a manually operable throttle valve has amechanilcal'linkagev with a venturi regulan-1eas te the cross sectional areaA thereof, the ventnri being fully closed whenthe' throttle valve is at minimum or'. closed throttle. Closingdf the'venturiiseeetive to. closeVv oifv completely one'o'r" rnorc main fuel nozzles, with an' idler! fuel nozzle being' left open in' the closed' throttle position.

Thek main fuel nozzle and i'cllerf` nozzle" are separately connected in communication with a' fuel supply bowl having a' constant liquid l'evel, and mountedin said bowl is an' acceleration' pump having a mechanical linkage' to the throttle valve sb' arranged as` to' cause said pump to operate only after the" tlirottle valvehas been' shifted to a. partially open position, said pump being connected' iii communication" with` the" fuelair passageof the` carburetor Body, independently of thezmain and idlernezzles, and being so'linked tothe throttle `valve a's to force an added quantity of fuel into the' carburetorbody'after movement of the throttlevalve' to atsele'eted, partially 'open position. Completing the construe tion`is1 a; vacuurnloperated piston connected to thel manifoldof" an' engin' on" which the carburetor is mounted; said piston being" disposed in an arrangement in which it isL linkedi mechanically to a metering rod that" controls' flow thro'u'gh` th'e' rriai'n fuel nozzle, thus to lean the mixture when" tlie'engineis oper# ating under a light load', and enrich the'A mixture when the engine is under `heavy load;

The broadobject of the invention is'to provide a' generally improved: carburetor" which' will' result inv a' more eflcient vaporization of `fue1',th`r'ough the tis'e of a venturi variable astoA cross sectional area andhavin'ga positive connection to the'throttle" valve. It may be noted, in this connection', that tliel veloct'yfofthe air in the venturi will, in accordance.- with the invention, be increased at low throttle openings, with the result'b'eing` that increased gasoline' mileageis obtained, and' engine response is more positive;

Another important object'of'theinvention is to provide a carburetor' construction which will, withoutr modication or redesignin'g'thereof, be' used' to advantage either on conventional passenger car engines, or'4 racing car engines in which one" or multiplecarburetorinstallations-may be utilized',

Another important object'is" to provide a carburetor construction asi statedf in which the acceleration pump will be so arranged, relativeto' cooperating parts of the carburetor, as to increase'A acceleration ofhigher throttle openings; said pump serving' the' further useful purpose of causing a coldenginel to operate moresmoothly;

Yet: anotherobject is-'tol' provide'l aA carburetor constructionas: stated.; in: which lAthos vacuum-operated means for regulating the quantityofffuelafed through- ,the main fuel nozzle will serve as amautoratically; operating-1 mixture control which, when used in conjunction with the ab'o'v'efmentioned acceleration pump, will eliminate the necessity of a separate choke valve such as is provided in conventional carburetors.

Other objects will appear from the following descrip; tion, the claims appended thereto, and from the annexed drawings, in which like reference characters designate like parts throughout the several views, and wherein:

Figure l is a top plan View of a carburetor formed in accordance with the present invention;

Figure 2 is a side elevational view;

Figure 3 is an elevational View of the carburetor as it appears when viewed from the left of Figure 2;

Figure 4 is a sectional view on line lL-'4` of Figure 3; y

Figure 5 is a longitudinal sectional view throughthe fuel supply bowl, taken substantially on line 5`-5 of Figure l;

Figure 6 is a longitudinal sectional view through the body o-f the carburetor, taken substantially on line 66 of Figure 3; and

Figure 7 is a transverse sectional View through said body, taken substantially on line 7-7 of Figure 6 Referring to the drawings in detail, the carburetor constituting the present invention includes a hollow body formed open at its opposite ends, said body including, at one end, a base portion l@ of circular cross section, said base portion being formed with an outwardly directed mounting flange l2 having diametrically opposite operi'- ings lid, said openings being adapted to receive bolts or other fastening elements, not shown, whereby the carburetor is connected to the intake manifold of an' internal combustion engine, also not shown.

The base portion 1i) of the body is integral with; arid merges into, a venturi portion designated generally at 1'6,. The venturi portion, as may be noted from Figure7, is generally rectangular in cross section, having flat, parallel side Walls 18 and a xed venturi wall 20 integral with and extending between said side walls. A s may benoted from Figure 6,- the fixed venturi wall 20 is preferably curved in the direction of its length, inwardly of the' fuelair passage defined by the hollow carburetor body.

As may be particularly noted from Figure l', the xied venturi wall and the side walls are formed, at their upper ends, with outwardly directed flanges, said an'gesm'erging into one another to provide a ared fomiationupoir that end of the'carburetor body that isl remote from the manifold, thus to form the carburetor with an air horn through which air will be drawn during operation of the'engi'n'e, to be intermixed with fuel fed into the body` To rigidify the body formation, a" crossbar 2`4`lc'an be used (Figure 6), said cross barbeing Iixedly` connected at its opposite' ends to the respective side walls 18" and extending therebetween, in' spaced relation tothe Xed Venturi'wall 2i).

Formed integrally upon the respective side wallslsare quadrantal, laterally projected side wall extensions`26, said side wall extensionsy being integrally or otherwise rigidly connected to an arcuate web 28 extending therebetween.

A throttle valve 3d of the butterfly type is pivotally mounted on a throttle valve shaft 3v2"extending diametrically thereof, the throttle valve shaft being journaled the wall of the cylindrical base portion 10.` One endfof the throttle valve shaft projects av substantial distance beyond the wall of the portionV l@ (Figure 7) and xedly connectedA to the projecting end is a split clamping ring 34 having spaced ears 36', 33betweenwhich a clamping'screw 40 extends. The clamp 3d can be adjusted to selected positions of'rotatable adjustment upon the shaft3'2, and can be? aiiixed to the shaftin ea'chipositionitowhich it'fis adjusted, by drawing of the ears 36, 38 toward' one aitl'ir through `thefrnedium'of the-screw 402` Integral with the ring 34 is an arm 42 (Figure 4) extending approximately radially from the shaft 32 and having an angular extension 44 on its free end. The Aextension 44, at one end, has a laterally offset ear carrying a connecting pin 46 formed with a ball at one end, said ball being adapted for universal connection to a throttle control cable, not shown. The throttle control cable, of course, would be operable by depression of an accelerator pedal or by operation of an equivalent operator-controlled means.

It is desirable that swingable movement of the arm 42 in one direction be limited, and to this end, a screw 48 is threadedly engaged in and is disposed longitudinally of the angular extension 44 of said arm 42, said screw 48 being threadable to selected positions longitudinally of the extension 44, and being engageable against an abutment 50 formed upon the wall of the carburetor body. It will be understood that the screw 48 will engage the abutment 50 when the throttle valve 39 is in the closed position shown in Figure 6.

The closed throttle position, of course, can be adjusted as desired, by threaded adjustment of the screw 48 relative to the extension 44.

In Figure 3, I have shown an idler fuel nozzle 52 opening into the carburetor through an aperture 53 (Figure 6), the fuel nozzle opening into said carburetor between the throttle valve 30 and the intake manifold of the engine on which the carburetor is mounted. The fitting 52 is provided with a connecting fitting 54, having a valve seat therein, said valve seat being adaptedto receive a needle valve 56, which needle valve constitutes an idle adjustment screw. It will be understood that the amount of fuel directed through the idler fuel nozzle 52 can be regulated by rotation of the screw 56 to selected positions, said screw being threadely engaged in the fitting 54 and being retained in selected positions to which it is threadedly adjusted by means of a spring circumposed thereabout.

Extending from the fitting 54 is an idler fuel supply tube 58, said tube 58 extending from a fuel supply bowl designated generally at 66, the bowl being tixedly connected in any suitable manner to one of the side walls 18 of the carburetor body.

Intermediate its opposite ends, the idler fuel supply tube 58 has an aperture 62, said aperture dening an air bleed opening or idling vent, for intermixing air with fuel flowing through the tube 58.

From what has so far been illustrated and described, it is seen that fuel will be supplied to the carburetor body,

at a location between the throttle valve and the intake manifold of the engine, for idling purposes, said fuel being supplied to carburetor body in the closed or minimum throttle setting of the manually-operable throttle valve.

Referring now to Figure 6, there is illustrated an air intake control valve in the form of a movable venturi wall 64, which, together with the fixed venturi wall 2t), defines a venturi intermediate opposite ends of the carburetor body. The movable venturi wall is formed as a fiat piece of metal material one end of which is of plane formation and wipes over the arcuate web 28, the other end of the movable venturi wall being longitudinally curved and being adapted to swing into and out of contact with the fixed venturi wall 20. The movable venturi wall, intermediate its opposite ends, is pivotally mounted upon a venturi rock shaft 66 journaled at its opposite ends in the side walls 18.

The movable venturi wall, when swung to selected positions relative to the fixed venturi wall, cooperates with said fixed wall in adjusting the cross sectional area of the venturi. In this connection, the venturi is mechanically linked to the throttle valve 30, so as to cause said cross sectional area of the venturi to be automatically regulated, responsive to shifting of the throttle valve to selected settings.

Reference should nowbe had to Figure 2, wherein the 4 mechanical linkage between the throttle valve and movable venturi wall is shown. As shown in this figure of the drawings, said linkage includes a radial arm 68 secured at one end to the adjacent end of the throttle valve shaft 32, for swinging of said radial arm responsive to rotation of the throttle valve shaft.

The arm 68, at a location remote from its fixed connection to the shaft 32, has a universal connection to one end of a longitudinally extensible link 70 connected universally, at its other end, to the outer end of a radial arm 72 secured fixedly to the venturi shaft 66.

It will thus be seen that movement of the throttle valve 30 away from its closed throttle position is effective to swing the movable venturi wall 64 out of contact with the xed wall 20 of the venturi, thus to open the venturi. Continued movement of the throttle valve 30 from closed throttle is effective to increase the cross sectional area of the venturi. I

The linkage between the venturi and the throttle valve is so adjusted as to cause the venturi to open at a slower rate than the throttle valve.

When the venturi opens by movement of the movable wall 64 away from the fixed wall 20, there will be opened one or more main fuel nozzles 74 (Figure 6). The main fuel nozzle 74 is mounted upon the fixed wall 20, and discharges into the fuel-air passage of the venturi. The movable Wall 64, as will be noted from Figure 6, is so disposed as to close the nozzle 74 when said movable wall is in full contact with the fixed wall 20. Thus, the supply of fuel to the carburetor through the main fuel nozzle 74 is stopped whenever the venturi is in its fully closed position. In any open position of the venturi, however, even a position in which the cross sectional area of the venturi is quite small, fuel will be delivered to the interior of the carburetor body through the main fuel nozzle 74.

The main fuel nozzle 74 is connected in communication with a main fuel supply tube 76. This is believed to be best shown in Figure 2, and in Figure 3. The main fuel supply tube 76 extends from a threaded connecting fitting 78 (Figure 4), that is threadedly engaged with a boss 80 integrally formed upon the bottom wall of the fuel supply bowl 60. The boss 80 has a main fuel outlet opening 82 that is in communication o with the bore of the fitting 78.

A metering rod 84 is vertically shiftable within a metering rod sleeve 86 aiiixed to the bottom wall of the fuel supply bowl, and extending upwardly within said bowl. The sleeve 86, at that end thereof that is connected to the bottom wall of the fuel supply bowl, has an opening 88, and it will thus be seen that movement of the metering rod to an open position, away from the fitting 78, is adapted to permit fuel to flow through the opening 88 into the fitting 78, and thence through the main fuel supply tube 76 and main fuel nozzle 74. When, however, the metering rod 84 is in the position thereof shown in Figure 4, it closes the opening 82 of the boss 807 thus to prevent fuel from flowing to the main fuel nozzle.

The fuel supply bowl 60 s provided with a removable cover 90 which is sealably connected to the receptacle portion of the bowl under all normal conditions.

The metering rod 84 projects upwardly through an opening formed in the cover 90, the projecting part of the rod having a nut 92 which can be threaded longitudinally of the rod for adjusting the normal position of the rod, said nut further serving as a stop limiting movement of the rod toward its seated or closed position.

The projecting portion of the rod 84 is apertured, and extending through the aperture is a cross pin 94. The pin 94 extends through one end of a link 96, thus to pivotally connect said link to the metering rod.

Aflixed to the link 96 is a link extension 98, said extension 9S being extended at an incline, transversely of the carburetor body, as shown in Figure 3. The link 9S is pivotally connected, by means of a pin 100, to one end of. anactuatingA 102;.. Link 1021 has a lost-motion connection to the pin 100, the purpose of thiszconnection being. to, permit'. movement. of the actuating link in the direction of its length, relative to the pin 100, for a predetermined extent' before said lengthwise movement transmits movement to the link 98 for elevating the metering rod 8:4.`

As will be noted from Figures 3- and 2, a spring 104 is circumposed about that. end ofthe actuating link 102 that is connected to the pin 100, said spring being slightly compressed whenever the actuating link 102 is shifted upwardly, after which the spring will transmit movement to the link.98.

Nuts 106 are threaded upon the link 102, and can be adjusted toward and. away from one another so as to connect the link 102 to the: pi'n100 inselected' positions, one of said nuts further serving to adjust the tension of the spring 104.

That end of the actuating link 102 remote from the pin is formed with a' lateral extension (Figure 3), said extension having a spring 108 circumposed thereabout and being projected through an' opening formed in the outer end of the radial arm 68. A cap is threaded upon the lateral extension ofi the link, thusv to permit a certain looseness in the pivotal. connection between the armY 68 and the link 102, while still normally maintaining said arm and link against excessive looseness relative to oneanother.

It will thus be seen that whenever the throttle valve 30 is shifted from closed throttle by the operator, the metering rodY 84 will be lifted4 from its. seated position, thus to permit fuel to flow through the main fuel nozzle intothe fuel-air passage ofthe carburetor body.

The invention includes means for supplying an added quantity of fuel after the throttle has been moved beyond a selected, partially open position, thus to increase acceleration at higher throttle openings, and also make for smoother and more efficient operation of a cold engine'. This means includes an acceleration pump mounted in the fuel supply bowl 60, and having a mechanical linkage to L the throttle valve that will cause pump operation in selected open positions of the throttle valve.

The linkage in question includes an elongated, longitudinally curved acceleration pump actuating rod 110 (Figure 2) pivotally connected at one end tothe arm 68, in closely spaced relation to the fixed connection of said arm 68 to the throttle valve shaft 32. The rod 110, at its other end, has a tlat formation that is provided with a longitudinal slot 112, receivingl one end` of a crank arm 114 formed upon a rock shaft 116 journaled rotatt ably in a rock shaft support sleeve 118 (Figures l and 6) axed to and extendingv in closely spaced parallel relation to the cross bar 24.

The slot 112 provides a lost-motion connection, and it will be seen that initial movement of the throttle valve 30 from its closed throttleposition toward its fully open position will not be effective to cause rotatable movement of the rock shaft 116. When, however, the throttle valve moves beyond a selected partially open position, the crank arm 114 will be engaged by one end wall of the slot 112, and will be swung to an extent suicient to transmit rotatable movement to the rock shaft 116.

The rock shaft 116, at that end thereof remote from the crank arm 114, has a radial arm 120 rigidly connected thereto, and pivotally connected at one'end to the free end of the radial arm'120 is arlink 122, which is pivotally connected at its other end to a rock arm 124 pivotally connectedintermediate its ends to a pivot bolt 126 projecting laterally from a pivot bolt support bracket 128 formed upon the cover 90 of the fuel supply bowl.

That end of the arm 124 remote from the link 22 (see Figure 4) is connected to a depending piston rod130 reciprocable in a piston rod-support sleeve 132, that extends downwardly within a: piston` cylinder 134 upstanding fromtthefbottom wall ofthe 4fuel/supply bowl-.601-

6 Carried by the lower end of the rody is a piston 136 working within thecylinder 134, a spring 138y being interposed between the bottom wall of the fuel supply bowl and said piston 136, so as to normally urge the piston 13 6 Vaway from the bottom wall of the fuel supply bowl.

extends from the block 144 and opens into the fuel-air passage of the carburetor body, between the venturi and the air horn.

The check valve 146, as will be seen from Figure 6, is so arranged as to permit fuel to flow from the auxiliary supply tube 142 to the carburetor, while preventing return flow of fuel to the acceleration pump;

Considering the operation of the accelerator pump, it becomesV apparent that after the throttle valvel 30 has moved' beyond a selected, partially open position, the piston 136 will be depressed within the cylinder 134, which will previously have been charged with a supply of fuel. Depression of the piston 136 is effective to force said fuel through the auxiliary supply tube 142, to the'carburetor.

This arrangement is desirable, in that it increasesv acceleration at higher throttle openings, and also improves operation of the engine, when the engine is cold.

Means is also embodied in the illustrated construction for. controlling the leanness or richness of the mixture fed to the engine by the carburetor, responsive to the particular condition of the load under which the engine is operated. To this end, I provide a vacuum cylinder 1'50 aixed to one wail of the fuel supply bowl, and having an: opening inone end communicating with a vacuum line 152 extending into communication with the base portion 10, between the throttle valve 30 and theintake manifold of the vehicle engine. A vacuum cup 1'54` is slidably mounted iny the'cylinder 150, movement of the vacuum cup inwardly of the cylinder being limited by a stop lug 156 carried by the cup and engaging against the outer end of the vacuum cylinder. A longitudinal slot- 158 is formed in the wall of the vacuum cylinder, and projecting through said slot is a stud 160 Vformed upon the vacuum cup. lt will be seen that the stud 160, and slot 158, cooperate to limit movement of the vacuum cup in opposite directions, longitudinally of4 its associated cylinder 150.

For the purpose of adjusting the vacuumy cup 154 longitudinally of the cylinder 150, I provide (see Figure 3) a vacuum cup adjusting means includinga bell.` crank having a longitudinal slot 162 in one leg thereof, said bell crank being designated by the reference numeral 164 and being pivoted upon a bolt 166 that extends outwardly from the fuel supply bowl. 60. At its other end, the bell crank 164 has an opening 168 adapted to receive one end of an adjusting cable or the like, not show-n, whereby the bell crank canbe swung upon itspivot 166 to selected positions.

The stud 160 extends into the slot 162,. and it will be seen that adjustment of the bell crank I64 to selected positions upon its associated bolt 166 will be effective toshift the vacuum cup 154 to a predetermined' location, taken longitudinally of the vacuum cylinder 150.

Slidable within and relative to the cup 154 is a cylindrical, solid piston 170, said piston being normally urged outwardly of the cup by a spring 172, that is interposed between the inner end of the piston 170 and the inner end wall of the cup. Saidinner end wall of the cup has an opening. 174 communicating with the interior of the cylinder 150, as clearly shown in Figure 5.v

The outer endof the. piston 170' isi formed with" an axial, apertured projection 176, an elongated rod 178 extending through the aperture of said projection, and being loosely pivoted, at its other end, within an angular bracket 180 carried by the cover 90. Intermediate its opposite ends, the rod 17S is connected to one end of a link 182, said link extending normally to the rod 178 and being fixedly connected to the link 96.

The construction described immediately above is adapted to cause movement of the metering rod 84 toward and away from its seated position, responsive to the vacuum condition within the intake manifold. Thus, if the engine is Operating at low load, the vacuum within said manifold will be high, and under these conditions, the piston 170 will be drawn downwardly against the opposing action of the spring 172, thus causing, in turn, a lowering of the metering rod. This reduces the amount of fuel fed through the main fuel supply tube 76, thus to lean the mixture.

When, however, the engine is operating under a heavy load, as for example, when it is accelerating or is being operated at full throttle, the vacuum in the manifold will be low, and the spring 172, tending to expand, will elevate the piston 170, thus to raise the metering rod S4 and increase the amount of fuel fed into the fuel-air passage, in relation to the amount of air drawn into said passage through the air horn.

Means is also provided in the invention for maintaining the fuel within the bowl 60 at a constant, unvarying level. The fuel line 190 (Figure 5) will extend from the fuel supply of the vehicle, said line 190 being connected to a fitting 192 having an axial bore 194 in which slides a main valve 196. The valve 196 is secured to one leg of a bell crank 198, by a suitable pivotal connection, said bell crank 198 being pivoted upon a pin 200 journaled in the opposed walls of the fuel supply bowl 60. The other leg of the bell crank is provided with a fioat 202.

The float 202 is so arranged as to cause the valve 196 to move to open position, whenever the fuel level within the bowl 6G drops to a predetermined extent. As soon as the bowl is refilled to a selected extent, the valve 196 will move to its closed position.

It is believed apparent that the invention is not necessarily confined to the specific use or uses thereof described above, since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of the principles of operation and the means presently devised to carry out said principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claims.

What is claimed is:

l. In a carburetor, a hollow body having upstanding walls open at both ends to define a continuous air-fuel passage therethrough, one end of said body formed as a throat connectable to an engine manifold and the other end open to the atmosphere, a throttle valve mounted in said throat for movement about an axis extending transversely therethrough to open and close said passage, an air intake control valve mounted in said passage between said throat and said other end of said body for movement about an axis extending transversely through said body parallel to said first-mentioned axis into engagement with adjacent portions of opposite walls of the body to bridge and close said passage and to define a movable venturi wall, one of said opposite walls defining a fixed venturi wall which along with said movable venturi wall defining a venturi of regulatable cross sectional area, a fuel nozzle opening into said venturi carried in said fixed wall and being closed when engaged by said movable wall, and linkage operatively connected between said throttle valve and said air intake control valve to open said nozzle and vary the cross sectional area of the venturi in proportion to the opening of said passage effected by movement of said throttle valve.

2. ln a carburetor, a body open at both ends to define a continuous air-fuel passage therethrough, one end of said body formed as a throat connectable to an engine manifold and the other end open to the atmosphere, a throttle valve mounted in said throat for movement about an axis extending transversely therethrough to open and close said passage, an air intake control valve mounted in said passage between said throat and said other end of said body 'for movement about an axis extending transversely through said body parallel to said first-mentioned axis into engagement with adjacent portions of opposite walls of the body to bridge and close said passage and to define a movable venturi wall, one of said opposite walls defining a fixed venturi wall which along with said movable venturi wall defining a venturi of regulatable cross sectional area, a fuel nozzle opening into said venturi carried in said fixed wall and being closed when engaged by said movable wall, and linkage operatively connected between said throttle valve and said air intake control valve to open said nozzle and vary the cross sectional area of the venturi in proportion to the opening of said passage effected by movement of said throttle valve, a fuel supply bowl carried by said body adjacent thereto, means for communicatingly connecting said fuel nozzle to said bowl for supplying fuel to said fuel nozzle, said means including a metering device for controlling the fiow of fuel, and a linkage operatively connected between said throttle valve and said metering device for operating said metering device in response to movement imparted to said firstmentioned linkage controlling the flow of fuel through said fuel nozzle in response to movement of said throttle valve from its closed position.

3. ln a carburetor, a body open at both ends to define a continuous air-fuel passage therethrough, one end of said body formed as a throat connectable to an engine manifold and the other end open to the atmosphere, a throttle valve mounted in said throat for movement about an axis extending transversely therethrough to open and close said passage, an air intake control valve mounted in said passage between said throat and said other end of said body for movement about an axis parallel to said first-mentioned axis into engagement with adjacent portions of opposite walls of the body to bridge and close said passage and to define a movable venturi wall, one of said opposite walls defining a fixed venturi wall which along with said movable venturi wall defining a venturi of regulatable cross sectional area, a fuel nozzle opening into said venturi carried in said fixed wall and being closed when engaged by said movable wall, and linkage operatively connected between said throttle valve and said air intake control valve to open said nozzle and vary the cross sectional area of the venturi in proportion to the opening of said passage effected by movement of said throttle valve, a fuel supply bowl carried by said body adjacent thereto, means for communicatingiy connecting said fuel nozzle to said bowl for supplying fuel to said fuel nozzle, said means including a metering device for controlling the fiow of fuel, and a linkage operatively connected between said throttle valve and said metering device for operating said metering device in response to movement imparted to said first-mentioned linkage controlling the flow of fuel through said fuel nozzle in response to movement of said throttle valve from its closed position, and means carried by and in communication with said fuel bowl for increasing the amount of fuel introduced into said passage after said throttle valve has been moved to beyond a predetermined partially open position, said last-mentioned means including an accelerator pump for drawing fuel from said bowl, a tube connected at one end to said pump and opening into said passage at its other end between said air control valve and said other end of the body, and

linkage means operatively connecting said pump with said throttle valve and operative upon movement of said throttle valve to said predetermined position to cause said pump to force fuel drawn from said bowl through said tube and into said passage.

4; In a carburetor, a body` open at both ends to define a continuous air-fuel passage therethrough, one end. of said body formed as a throat connectable to an engine manifold and the other end open to the atmosphere, a throttle valve mounted in said throat for movement about an axis extending transversely therethrough to open and close said passage, an air intake control valve mounted in said passage between said throat and said other end of said body for movement about an axis parallel to said rst-mentioned axis into engagement with adjacent portions of opposite walls of the body to bridge and close said passage and to define a movable venturi wall, one of said opposite walls defining a fixed venturi wall which along with said movable venturi wall defining a venturi of regulatable cross sectional area, a fuel nozzle opening into said venturi carried in said fixed wall and 4being closed when engaged by said movable wall, and` linkage operatively connected between said throttle valve and said air intake control valve to open said nozzle and vary the cross sectional area of the venturi in proportion to the opening of said passage effected by movement of said throttle valve, a fuel supply bowl carried by said body adjacent thereto, means for communicatingly connecting said fuel nozzle to said bowl for supplying fuel to said fuel nozzle, said means including a metering device for controlling the ow of fuel through said means, and a linkage operatively connected between said throttle valve and said metering device for operating said metering device in response toxgfmovement imparted to said first-mentioned linkage controlling the ow of fuel through said fuel nozzle in respons to movement of said throttle valve from its closed position, and means carried by and in communication with fuel bowl for increasing the amount of fuel introduced into said passage after said throttle valve has been mtied to beyond a predetermined partially open position, said last-mentioned means including an accelerator pump for drawing fuel from said bowl, a tube connected vat one endl to said pump and opening into said passage at its other end between said air control valve and said other end of the body, and linkage means operatively connecting said pump with said throttle valve and operative upon movement of said throttle valve to said predetermined position to cause said pump to force fueldrawn from said bowl through said tube and into said'fpassage, and vacuum operated means in communication with said throat and operatively connected to said metering device for regulating the amount of fuel owing into said device in response to vacuum changes in the manifold due to changing load conditions.

References Cited in the tile of this patent UNITED STATES PATENTS 1,360,445 Rollins Nov. 30, 1920 1,555,489 Spencer et al. Sept. 29, 1925 1,802,321 Mabee et al Apr. 21, 1931 2,052,225 Hartshorn Apr. 25, 1936 2,118,220 Mock May 24, 1938 2,619,333 Carrey Nov. 25, 1952 

